By Leah Kerkman Fogarty
Mason psychologist Koraly Perez-Edgar is a voice for all the shy kids out there. Since graduate school, she has studied temperamentally shy children and their psychophysiological traits, such as brain activation, stress hormones, and cardiovascular activity.
Shy kids, she says, have an early predisposition to anxiety, which, if it remains unchecked, puts them at an increased risk for internalizing disorders, particularly clinical anxiety.
“My interest, when I was a grad student, was to look at some of the things that moderate this trajectory, because the vast majority of these kids don’t go on to have an anxiety disorder, ” explains Perez-Edgar, assistant professor of psychology and head of the Cognition, Affect, and Temperament Lab at Mason.
She specifically looks at attention mechanisms in these children and what she calls their “attention biases to threat.” Attention, she says, is the gatekeeper to how people—children and adults—process an event.
“Once we attend to something, then we process it, then we interpret it, and then we respond to it,” Perez-Edgar explains. “Attention therefore creates the experienced environment for the child. If that experienced environment is biased in some way, that creates a reinforcing cascade of events that over time can make a child who’s vulnerable travel even further toward anxiety.”
“Some kids are just naturally biased toward finding or interpreting threat in their environment and withdrawing as a result,” she says.
For example, imagine you invite a friend to a movie. Say, she declines, saying she’s too tired or too busy. If you have a bias toward threat, then you may interpret this as a slight—that your friend really doesn’t like you or doesn’t want to spend time with you.
Perez-Edgar and her team create this sort of situation in their testing, which they call a “play date.” They lead five-year-old test subjects through a series of “games,” which are really tasks that measure the kids’ levels of attention and perceived threat.
During the play date, kids wear an EEG cap “so that way we get their brain response to rejection and acceptance,” Perez-Edgar says. “We see how well they do under both positive and negative feedback so we measure their behavior under stress.”
In addition to this Mason-based study, Perez-Edgar has been involved with a multiperson, longitudinal study at the University of Maryland since 1998, which has followed a cohort of children from the time they were 4 months old until they were 19 years old. Through this study, she’s had the opportunity to see how these temperamentally shy kids evolve over time.
Jerome Kagan, Perez-Edgar’s graduate advisor at Harvard University, and one of his former graduate students, Nathan Fox at the University of Maryland, started these kinds of studies with children at Harvard. “They bring in kids just when their personalities are beginning to show, around four months,” says Perez-Edgar. “You show them novel stimuli: some kids love it, others scream their heads off. So we selected the extremes of those kids, and we followed them over time.”
They’ve been able to determine a lot about these kids.
“We now know they have increased levels of anxiety. They have a greater startle response and greater levels of stress hormones,” says Perez-Edgar. This cohort of children has also provided data for studies on reward processing, social rejection, and the role of genetics.
The team was also able to confirm a long-held assertion about temperamentally shy children: that they have a hyperactive amygdala, the part of the brain that processes threat and is central to the “fear circuit.”
But, overall, the news is encouraging for the future of these shy kids.
“Left to their own devices, most children naturally outgrow their extreme temperamental shyness,” says Perez-Edgar. “It’s only a small subset that stays anxious and becomes clinically anxious.”
So what is it that allows most of these children to be happy and healthy but causes a few of them to remain withdrawn up until the point where they become clinically anxious? Perez-Edgar says it’s partly their attention biases.
“It keeps pulling them back, it tethers them to this initial bias, this initial vulnerability,” she explains. American society doesn’t place a high value on being shy, Perez-Edgar says. “We want outgoing, exuberant kids. In the United States, parents really work at getting their kids to be less shy.”
As a result, most kids will get over their shyness unless, she says, their attention bias to threat is strong. “If you don’t have this attention bias, you’re much more open to parental and environmental forces that say, ‘Come out of your shell.’”
“Under neutral conditions, these kids don’t test any differently from children without inhibited behavior,” says Perez-Edgar. But when a level of stress is added—say, by telling them they’ll have to give an impromptu speech that will be videotaped and shown to their classmates if they don’t score a certain amount—then their bias toward threat and sensitivity to stress emerges.
“What we found was that for shy kids, their ability to perform plummeted. So it’s not that they’re normally deficient in attention processes, it’s that, under stress, they can’t really marshal these attention processes for their benefit.”